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ix                    PHEN-ACODUS AND THE CREODONTS                 2O3
the details of its osteology. It was not a, large creature (see
Fig. 110, p. 196), about 6 feet in length, with a small head.
The feet were more or less plantigrade, and five-toed. The last
phalanges of the toes show that they carried hoofs and not
claws ; yet the fore-feet look a little as if they could be used as
grasping organs. The third digit of both hind- and fore-feet
exceeds the others, and tlius a Perissodactyle-like foot characterised
this Eocene creature. The tail is exceedingly long, and must
have reached the ground as the animal walked. This is of course
by no means an Ungulate character. Still, in the totality of its
organisation the animal was decidedly Ungulate, though Professor
Cope spoke of PJienacodus as not merely an ancestral Ungulate
but as the parent form of Insect!vores, Carnivores, Lemurs,, Monkeys,
and Man himself I The scapula indeed is from its breadth and oval
contour rather like that of a Carnivore. The clavicles as in other
Ungulates are absent. The femur is Perissodactyle rather than
Artie-dactyl e in the presence of a third trochanter. The creature
had fifteen pairs of ribs and five or six lumbar veitebrae. The
two bones of the leg which lie below the femur are perfectly
distinct and separate. A cast of the brain-case shows that the
cerebral hemispheres were smooth and small, the cerebellum of
course completely uncovered and nearly as large as the cerebrum.
The olfactory lobes were also large. The complete skeleton of
PhenacodMS has lately been excavated more fully from the
enveloping matrix by Professor Osborn,1 and mounted in what
is regarded as the natural position of the beast. It appears
that though five-toed it went upon the three middle toes only,
and furthermore that of these the middle one was the more
prevailing, so that Phenacodus was distinctly " Perissodactyle/*
at least in habit. Moreover its " long hind-quarters, the long
powerful tail . . . are reminiscent of Creodont ancestry." The
genus was European and American in range.
Meniscotheriutn (= Hyraoops2) comprises several forms of
about the size of a fox ; they are both European and American in
range. The teeth are more distinctly Ungulate in form than those
of Phenacodus, with a W-shaped outer wall. The skull is
described as possessing " indifferent, primitive characters/* permit-
ting a comparison with those of Opossums, Inseetivores, and
1  Bull. A'mer. Mw. Nat. Hist. x. 1898, p. 159.
2  Marsh, ~Amer. JToum,. Set. xlill. 1892, p. 447.